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  • 1
    Electronic Resource
    Electronic Resource
    Micellar Solutions Obtained with Amphiphilic Block Copolymers in the Presence of Water, Oil, and Alcohol. 1. Small Angle Neutron Scattering Structure Investigation in the Case of Poly(2-vinylpyridine-b-ethylene oxide) Block Copolymers (1979)
    s.l. : American Chemical Society
    Macromolecules 12 (1979), S. 1180-1186 
    Details
    ISSN: 1520-5835
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ma60072a033
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  • 2
    Electronic Resource
    Electronic Resource
    Cristallisation du poly(oxyéthylène) dans des copolymères séquencés, 2Partie 1: cf.1.. Étude de la structure et de la texture (1976)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 177 (1976), S. 199-212 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: The lamellar structure of a series of two-block poly(oxyethylene)/poly(ethyl methacrylate) and poly(oxyethylene)/polystyrene copolymers was studied by low-angle X-ray diffraction, as a function of the temperatures of crystallization and annealing.The thickness of the lamellae increases with temperature; the number of folds of the crystalline polymer chains varies, apparently, in a continuous way. The discontinuous increase of the thickness observed at 40°C in the annealing experiments was interpreted in terms of the glass transition temperature of the amorphous blocks.The spherulithic texture of the samples was examined by microscopy with polarized light.
    Notes: A l'aide de la diffraction des rayons X aux petits angles, on a étudié la structure lamellaire d'une série de copolymères biséquencés poly(oxyéthylène)/poly(méthacrylate d'éthyle) et poly(oxyéthylène)/polystyrène, soit en fonction de la température de cristallisation, soit en fonction de la température de recuit.L'épaisseur des lamelles croît avec la température, l'indice de repliement des chaînes cristallisées variant apparemment de façon continue. L'augmentation brusque de l'épaisseur observée à 40°C pour les expériences de recuit a été interprété en termes de débloquage des séquences amorphes au-dessus de la température de transition vitreuse.Par microscopie optique en lumière polarisée, on a examiné la texture sphérolithique des échantillons.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1976.021770115
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  • 3
    Electronic Resource
    Electronic Resource
    Micellisation de copolymères séquencés polystyrène-polyvinylpyridinium, 3Partie 2: cf.2; les résultats présentés dans cet article font partie de la thèse d'état de J. Selb, Université L. Pasteur, Strasbourg (1978).. Influence de la concentration en sel et de la température (1981)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 182 (1981), S. 1513-1524 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The effects of the salt concentration and temperature on the micellization phenomenon of polystyrene-poly(4-vinyl-N-ethylpyridinium bromide) block copolymers in dilute solution are investigated in solvents selective for the polyelectrolytic part (water-methanol-LiBr mixtures). The polystyrene moiety being in non-solvent media remains rather collapsed whatever temperature and salt concentration. On the contrary, the latter parameters modify strongly the conformation of the soluble polyelectrolytic chains and therefore determine the “quality” of the solvent essentially towards the polyvinylpyridinium blocks. Consequently an increase of the temperature or a decrease of the salt concentration have the same effect on the behaviour of the copolymers. In the case of a copolymer with a small molecular weight polystyrene block (Mw = 2 700), the unimer-multimer (single molecules/micelles) equilibrium is easily shifted in favour of the single molecules by increasing the temperature or decreasing the ionic strength. On the contrary, if the polystyrene moiety is longer (Mw = 6 000 - 13 000) the micellar weight of the system is little or even not at all influenced by the ionic strength and the temperature. These results emphasize that, for the investigated systems, it is the “insoluble” blocks which essentially govern the micellization phenomenon.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1981.021820522
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  • 4
    Electronic Resource
    Electronic Resource
    Synthèse et caractérisation de copolymères triséquencés de différents méthacrylates d'alkyle (1977)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 178 (1977), S. 107-118 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Triblock copolymers of different alkyl methacrylates with side chains containing 1 to 12 carbon atoms were synthesized by anionic polymerization in tetrahydrofuran with diphenylmethyl sodium or naphthalene sodium (sodium dihydronaphthylide) as initiators. The polymer samples were fractionated by means of solvent/non-solvent systems. Gel permeation chromatography (GPC), light scattering, osmometry, and elemental analysis were used to characterize the fractions. The copolymers were found to be free of homopolymers and the polydispersity of molecular weight of the fractions to be very low.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1977.021780111
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  • 5
    Electronic Resource
    Electronic Resource
    Micellar solutions obtained with amphiphilic copolymers in the presence of water, oil, and 2-propanol (1979)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 180 (1979), S. 1611-1615 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1979.021800625
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  • 6
    Electronic Resource
    Electronic Resource
    Etude systématique des «microémulsions;» obtenues avec des copolymères séquencés poly(vinyl-2 pyridine)/poly(oxyéthylène), 1. Domaine d'existence; Nature et composition des phases continue et dispersée (1984)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 185 (1984), S. 205-220 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A systematic investigation of transparent systems (“polymeric microemulsions”), obtained with amphiphilic block copolymers in the presence of water, toluene, and alcohol, was carried out. Their domain of existence in the pseudo-ternary phase diagram is limited compared to that observed for microemulsions with classical surfactants and located in the vicinity of the miscibility curve of the ternary solvents mixture. From dialysis equilibrium and viscosity measurements, it has been established that, whatever the respective lengths of the sequences are, these stable systems consist of a dispersed “phase”  -  containing the compolymer molecules  -  surrounded by an continuous “phase”. Both “phases” are composed of a mixture of the three considered solvents, the continuous phase being constituted by a ternary solvent mixture located on the mutual solubility curve. As a consequence, all water or oil is not trapped within the dispersed particles as in the case of classical micromulsions, but there is a preferential obsorption of the solvents by each type of blocks of the copolymer.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1984.021850118
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  • 7
    Electronic Resource
    Electronic Resource
    Synthèse et caractérisation de copolymères séquencés polystyrène/polydiméthylsiloxane et polyisoprène/polydiméthylsiloxane (1975)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 176 (1975), S. 1641-1656 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Polystyrene/polydimethylsiloxane and polyisoprene/polydimethylsiloxane block copolymers were synthesized by anionic polymerization in cyclohexane (styrene and isoprene) and in a cyclohexane-diglyme mixture (hexamethylcyclotrisiloxane) with the use of sec-butyllithium as initiator.Polymers have been fractionated from benzene solution by progressive addition of methanol. Gel permeation chromatography (GPC), light scattering, osmometry, and elementary analysis were used to characterize the fractions. Copolymers, thus prepared, are free of homopolymers and the polydispersity of molecular weight and composition of the fractions is very low.
    Notes: On a synthétisé à l'aide de la technique de polymérisation par voie anionique des copolymères biséquencés polystyrène/polydiméthylsiloxane et polyisoprène/polydiméthylsiloxane. On a effectué la polymérisation du premier monomère (styrène ou isoprène) en milieu cyclohexane avec comme promoteur le sec-butyllithium, celle du second monomère (hexaméthylcyclotrisiloxane) en milieu solvant binaire (cyclohexane-diglyme).Les échantillons ont été fractionnés par addition progressive de méthanol à leur solution dans le benzène. On a caractérisé les différentes fractions par chromatographie sur gel perméable (GPC), diffusion de la lumière, osmométrie et analyse élémentaire. On a montré que les copolymères bruts ainsi préparés ne renfermaient pas d'homopolymère et que les fractions recueillies présentaient une polydipersité très faible en masse moléculaire et en composition.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1975.021760609
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  • 8
    Electronic Resource
    Electronic Resource
    Étude du pouvior émulsifiant des copolymères séquencés polystyrène/chlorure de polyvinyl-2 pyridinium et polyisoprène/chlorure de polyvinyl-2 pyridinium (1976)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 177 (1976), S. 2773-2780 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: The emulsifying effect of polystyrene/poly(2-vinylpyridinium chloride) and polyisoprene/poly(2-vinylpyridinium chloride) block copolymers has been intensively studied. It has been shown that, in the presence of two non-miscible liquids, each of them being a selective solvent of one of the blocks, it is possible to obtain oil in water or water in oil emulsions, depending upon the molecular characteristics of the copolymers. More precisely, in the case of copolymers with high 2-vinylpyridinium chloride content, only oil in water emulsions have been obtained, whereas in the case of copolymers with a high styrene (or isoprene) content water in oil emulsions have been preferentially obtained.
    Notes: On a étudié de manière approfondie l'effet émulsifiant des copolymères séquencés polystyrène/chlorure de polyvinyl-2 pyridinium et polyisoprène/chlorure de polyvinyl-2-pyridinium. On a ainsi montré, qu'en présence de deux solvants non miscibles et sélectifs de chaque séquence, ces copolymères donnent des émulsions stables qui sont de type huile dans eau ou eau dans huile selon les caractéristiques moléculaires des copolymères considérés. Plus précisément, les copolymères à forte teneur en chlorure de vinyl-2 pyridinium conduisent uniquement à des émulsions huile dans eau, tandis que les copolymères riches en styrène (ou en isoprène) donnent préférentiellement des émulsions eau dans huile.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1976.021770918
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  • 9
    Electronic Resource
    Electronic Resource
    Distinction entre les phénomènes d'agrégation et de micellisation présentés par des copolymères amphipathiques. Cas des copolymères polystyrène/polyvinylpyridinium en milieu aqueux (1980)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 181 (1980), S. 809-822 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Hydrophobic-hydrophilic polystyrene/poly(4-vinyl-N-ethylpyridinium bromide) (poly-(l-phenylethylene)/poly[l-(N-ethyl-4-pyridinio)ethylene bromide]) block or graft copolymers were synthesized. These copolymers are well defined products, and are homogeneous in mole- cular weight and composition. They were obtained by quaternization, with ethyl bromide, of the nitrogen atoms of pyridine units of polystyrene/poly(4-vinylpyridine) block or graft copolymers. In dilute solution in a selective solvent for polyelectrolytic polyvinylpyridinium moities (water + salt), there is multimerization, i. e. presence of particles constituted by several macromolecules. Light scattering and ultracentrifugation measurements show that this multimerization is not the expected “micellization”, i.e. an “association” phenomenon due to the amphiphilic character of the copolymer, but corresponds Lo an “aggregation” phenomenon, resulting from incomplete dissolution of the product at the molecular scale.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1980.021810405
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  • 10
    Electronic Resource
    Electronic Resource
    Micellisation de copolymères séquencés polystyrène-polyvinylpyridinium, 2Partie 1: cf.2. Les résultats présentés dans cet article font partie de la thèse d'état de J. Selb, Université L. Pasteur, Strasbourg (1978).. Influence des caractéristiques moléculaires des copolymères (1981)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 182 (1981), S. 1491-1511 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The influence of the molecular characteristics of polystyrene-poly(4-vinyl-N-ethylpyridinium bromide) block copolymers (PS-PVPQ) on their dilute solution properties is investigated in a solvent selective for polyelectrolytic moieties (water-methanol-0,1 mol/1 LiBr mixtures). It is shown that the association degree depends much more upon the length of the insoluble hydrophobic part of the macromolecule than on the length of the soluble hydrophilic part. Micelle dimensions could not be determined from light scattering measurements because of the compactness of the particles. Attempts for the calculation of micelle size were made using a star-like micellar model.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1981.021820521
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